Induction-motor.



A. M. DUDLEY.

INDUCTION MOTOR.

APPLICATION FXLED NOV.8, 1911.

1,170,618. Patented Feb. 8, 1916.

3 SHEETS-SHEET lllzy. g

Wad/id ATTORNEY A. M. DUDLEY.

INDUCTION MOTOR.

APPLICATION FILED NOV. 8. 1911.

Patented Feb. 8 1916.

3 SHEETS-SHEET 2 IN ENTOR WITNESSES Ai'TORNEY A. M. DUDLEY.

INDUCTION MOTOR.

APPLICATION FILED NOV. 8, 1911.

Patented Feb. 8, 1916.

3 SHEETS-SHEET 3 INVENTOR Jdolgw M 000767 ATTORNEY UNITED STATES PATENT OFFICE.

ADOLPHUS Ms-DUDLEY, OF SWISSVALE, PENNSYLVANIA, ASSIGNOR T0 WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN- SYLVANIA.

INDUCTION-MOTOR.

Application filed November-8, 1911.

To aZZ whom it may concern:

Be it known that I, AnoLrHUs M. DUDLEY, a citizen of the United States, and a resident of Swissvale, in the'county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in-Induction-Motors, of whichthefollo'wing is a specification.

My invention relates to alternating current motors and has special reference to such motors as are-adapted for multispeed operation and are known as adjustable speed motors.

The object of my invention is to provide a motor of the class above indicated and a winding therefor that shall comprise a plurality of similar coils and shall embody a minimum number of externalcircuit leads, and particularly simple controlling means for adjusting the motor speeds.

My invention belongs to the same class as the inventions set forth in Alexanderson Patents Nos. 841,609 and 841,610, granted January 15, 1907, and is an improvement upon the subject matter of these patents.

In a-more limited aspect, my invention consists-in providing a polyphase winding for alternating current'multl-speed motors having each phase or branch of the winding formed of uniform overlapping coils connected in two roups; theone comprising those coils which remain in the same phase or branch for more than one motor' speed, and the other comprising those coils which changefrom one phase or branch to another in changing'from one motor Speed to another, suitable means being provided for effecting the necessary changes in the group connections.

It will be clearly understood by those Specification of Letters Patent.

Patented Feb. 8, 1916;

Serial No. 659,150.

s a diagrammaticview of a two-phase windlng arranged in accordance with my invent on, particularly illustrating the arrangement of groups. Fig. 2 is a diagrammatic V ew lllustrating the distribution of coils. Fig 8 shows the motor winding of my invention developed into a single plane. Figs. 4 and 5 are views corresponding, respectively, to F igs. 3 and 1 of a three-phase T- connected winding embodying my invention. Fig. 6 1s a diagrammatic View illustrating the directions of the current traversin the several coils atthe same instant. Figs. 8 are diagrammatic views illustrating the connections of the motor winding as establlshed by the controlling switch of Figs. 4 and 5. I

Assuming that a tw0-speed winding as and shownin the drawings, to whichreference for changing the speed. In fact, when the winding is T-oonnected, as indicated in Fig. '4, it is possible tomake one of the connections between groups permanent and,,consequently, only seven leads are brought out when the motor is adapted to operate on a three-phase circuit.

In Fig. 1, coil group 1 is always connected to phase or branch one of its terminals being permanently connected by conductor 2 to supply-circuit terminal 3 and the oppo skilled in the art that it is highly desirable v site terminal being connected, through conto reduce the number of external leads with which the winding is necessarily provided,

in order to simplify the speed-controlling 6. Coil group 7 is always connected to ductor 4, to contact finger 5 ofa controllermechanism and the motor connections. By the use of my present invention, I reduce the number of groups into which the winding is necessarily divided, from a minimum of four per phase or branch to a minimum of two per phase or branch. By reason of its simplicity, the winding is adapted for,a

very much wider application than windings of the same general class heretofore developed.

Figure 1 of the accompanylng drawlng phase or branch B, one of its terminals bemg permanently connected,-through conductor 8, to supply circuit terminal. 9, and its; opposite terminal being connected, through conductor 10, to control finger 11. Coil groups 12 changes from phase or branch-A to phase or branch B, its terminals being respectively connected, through conductors 13 and 14, to-contact-fingers 15 and 16. Coil' group 17 changes from phase or branch B to phase or branch A, its terminals being respectively connected, through conductors'18 and 19, to contact fingers and 21. v

The controller 6 is adapted to occupy an intermediate ofi' position, as shown,- and two closed circuit positions a and b. When the controller occupies position a, a circuit is completed from terminal 3 of phase A through conductor 2,.coil group 1, conductor 4, contact fingers 5 and 15 (which are bridged by contact member 22) conductor 13, coil group 12, conductor 14, contact finger 16, contact member 23 and conductor 24,

to opposite line terminal 25. A circuit is similarly completed from terminal 9 of phase B through coil groups 7 and 17. to the opposite terminal 26.

When the controller occupies position b,

- a circuit is completed from terminal 3 of phase A through conductor 2, coil group 1,

conductor 4, contact fingers 5 and 20 (which are bridged by a contact member 27) conductor 18, coil group 17, conductor 19, contact finger 21,'contact member 28 and conductor 24, to opposite line terminal 25'. A circuit is similarly completed from terminal 9 of phase B through coil groups 7 and 12. Thus it appears that, for one motor speed, coil groups 1 and 12 are connected in one phase or branch of the'winding, and coil groups 7 and 17 in the other, while, torthe other motor-speed, coil groups 1 and 17 constitute one phase or branch of the winding and coil groups 7 and-12 the other.

Referring to Fig. 2, the coil groups are divided into individual'coils distributed as they would appear in the primary of an induction motor. It will be observed that the coils are so arranged and connected as to produce poles of only one polarity, the poles of opposite polarity resulting naturally or consequently between the poles for which the coils are wound. Twenty-tour coils are shown and are numbered, consecutively,

from 31. to 54. Coils 31, 32, 33, 39, 49 and 50 constitute group 1, coils 34, 40,41, 42, 47'- trol device are arranged for connecting the winding to a three-phase source of supply, a T-connected arrangement of the coil group being maintained so that there are only two branches, as in the two-phase system, the coil groups being determined similarly according as the coils remain in one branch of the winding or the other, or are changing from one branch to the other, as the motor-speed is adjusted.

Referring to these figures in which the coils and the coil groups are designated by the same reference characters as in Figs. 1, 2 and 3, one terminal of coil group 1 is'connected to terminal 56 of a three-phase circuit, the opposite terminal of the group being connected to contact finger 57 of a speed controlling switch 58. The adjacent terminals of coil groups 7 and 12 are permanently interconnected and are connected to a contact finger .59 through conductor 60. The free terminal of group 12 is connected to contact finger 61, and the free terminal. of group 7 is connected to line terminal 62.

The terminals of group 17 are respectivelyv connected to contact fingers 63 and 64. The

remaining line terminal 65 is connected t contact finger 66. y

The speed-controlling switch 58 is adapted to -occupy positions 0 and d, and, when in position 0, the coil groups are connected as follows: Groups 1 and 12 constitute one branch of the. l -connected winding, circuit being completed from line terminal 56 through group 1, fingers 57- and 61, and groups 12 to the point of connection between groups 7 and 12. Circuit is completed from line terminal 65 through contact fingers 66 and 64, group 1?,fingers 63 and 59, and conductor 69 to the same point of connection.

A third circuit is completed from circuitter minal 62 through group 7 to the same point of connection.

In Fig. 6 is shown a simplified'diagram of thecharacter employed for determining the coil connections in a circuit such as that shown in Fig. 2 which is arranged toprovide either six poles or eight poles. Each coil from 31 to 54, inclusive, is represented by an arrow, indicating by its position the center line of the, coil and by its direction the direction of current flow, at a given instant, in one'side of the coil, thev particular side chosen being the same in all cases. For six-pole operation, the twenty four coils are divided into six groups of four each, as indicated in the upper portion of Fig. 6, and said groups are further arranged in two rows marked respectively A and .B and corresponding respectively to the A and B phases in Fig. 1. In like manner,.for eightpole operation, the twentyfour coils are divided into eight groups, of three coils each, and these groups are also arranged in equal A and B phases.

' From an inspection of'the six-pole and eight-pole groupings, it will be noted. that coils 31, 32, 33, 39, 49 and 50. are in the A phase in each case and these coils may therefore. be connected together to form Winding 1 in Fig. 2. In like manner, coils 35, 36, 52, 53 and 54 are in the B phase in each pole grouping and these coils may accordingly be connected together to form the winding 7 in Fig. 2. The coils 34, 40, 41 42, 47 and 18 change from the A phase to the '13 phase in the transition from the SlX pole to the eight pole connection and are accordingly connected together to form the winding 12.

.having the same polarityat the same instant. The relative direction of current flow is not reversed in any of the groups of coils in changing from one speed to the other.

Figs. 7 and 8 illustrate, respectively, the connections of the several coil groups for the production of SlX poles and eight poles. Since the coil groups 7 and 12 arepermanently connected, a minimum of seven conductors may be employed. It will be noted that the groups 12 and 17 are changed from one branch to another Without relatively re .versing their respective terminal connections and therefore without reversing the relative direction of current-flow'in the coil groups 12 and 17. i

I am aware of the fact that, by causing the two phases A and B to have likenumbers of coils, a slightly distorted T connection is provided with consequent slight unbalancing but, for many classes of service, this effect may be neglected.

It is evident that theztotal number of coils in the winding and in the several groups will he determined by the service for which the motor is intended, and that other variations may be efiected-within the spirit and scope of my invention. a

I claim'as my invention:

1. A winding for polyphase multi-speed alternating current motors consisting of conductors so arranged that the current always flows in the same relative direction, and means for connecting said conductors to form a plurality of groups according as they belong to a single branch for all speeds, or are changing from one branch to another.

2. A winding for polyphase multi-speed alternating current motors consisting of coils so arranged that the current always flows in the same relative direction, and

means for connecting said coils to form a plurality of groups which,respectively, contain coils which remain in one phase for all speeds and those which change phase in passing from one speed to the other.

3. A winding for polyphase multi-speed alternating current motors consisting of coils in allof which the current continuously flows in the same relative direction to produce a plurality of consequent poles, said coils being permanently connected in groups according as they belong to one phase for all speeds, orchange from one phase to another when the motor speed is changed.

4. In a two-speed consequent-pole induction motor, the combination with a winding composed of coils arranged in groups and having said groups arranged in relatively displaced phases, of means for interchanging certain of said groups between said phases and for maintaining the relative direction of current flow in said coils.

5. A multi-speed winding for alternating current motors, arranged in T connection and comprising a plurality of uniformly distributed coils in two branches .of two groups each, and means for changing the connections of said groups without changing the relative direction of current in said direction of current in said groups, whereby a maximum of eight winding terminals is required.

7 A multi-speed winding for alternating current motors, arranged -in.T connection and consisting of two branches of two groups each, and means for changing the connections of said groups without changing the relative direction of current therein,

8. A multi-speed winding for alternating current. motors arranged in T connection and comprising a plurality of uniform, distributed coils divided into two branches of two groups each, the coils of each group being permanently connected, whereby a maximum of eight winding terminals is required.

9. A winding for polyphase multi-speed alternating current motors consisting of a lurality of conductors, means for connect- 1ng said conductors to form a plurality of groups according as they belong to a single branch for all speeds or are changed from one branch to another and for maintaining the relative direction of current-flow in said conductors.

10. A multi-speed winding for alternating current motors, consisting of a plurality of uniform distributed coils arranged to producepoles of like sign, said coils being divided into two branches of two groups each, the coils of each group being permanently connected and distributed in unequal sub-groups whereby a maximum of eight.

and means for changing said last-named groups from one branch to another and for maintaining the relative direction of current flow in said groups.

13;, A multi-speed winding for alternating current motors, arranged in T connection, a plurality of uniformly distributed coilsconnected in two branches oftwo groups each, two of said'groups being permanently connected together and means for changing the connections of said groups except at said permanent connection for varying thespeed of the motor without changing the relative direction of current in said groups, whereby only seven winding terminals are required.

In testimony whereof, I have hereunto subscribed-my name this 31st day of Oct,

ADOLPHUS M. DUDLEY.

Witnesses:

M. W; BARTMESS, B. B, Hmns. 

